1. Field of the Invention
This invention relates to an electrophoresis pattern analyzer for genetic material suitable for detection and identification of a gene, such as DNA, RNA and a material generated by the gene. The analyzer of this invention is applicable to disease diagnosis, parent-children judgment, physical constitution diagnosis, and cattle and plant breeding judgment.
2. Description of the Prior Art
The southern plotting method, the northern plotting method and the western plotting method have been known for analyzing electrophoresis patterns of a genetic material, such as DNA, RNA and proteins generated by genes (hereinafter referred to as generated proteins). These methods have been employed to detect and identify genes and generated proteins.
In all of these methods, a datum genetic material and a sample genetic material are disposed perpendicularly to the direction of electrophoresis, and are simultaneously effected to migrate electrically for a predetermined period of time. The result of the electrophoresis of the datum and sample genetic material is visually identified.
For instance, an electrophoresis specimen 100, as shown in FIG. 3, results from the southern plotting method. The electrophoresis specimen 100 comprises a datum region 101 defined by the electrophoresis region of the datum genetic material, and sample regions 102, 103 and 104 defined by the electrophoresis regions of the respective sample genetic materials. The datum region 101 has large and intense bands B1 and B2 at 1.35 kb and 1.15 kb of a coordinate axis in the direction of electrophoresis. The sample region 102 has a large and intense band B3 at 1.35 kb of the coordinate axis in the direction of electrophoresis. The sample region 103 has a large and intense band B4 at 1.15 kb of the coordinate axis in the direction of electrophoresis. The sample region 104 has small and slightly intense bands at 1.35 kb and 1.15 kb of the coordinate axis in the direction of electrophoresis. Here, kb, the unit of the coordinate axis in the direction of electrophoresis means a segment length of DNA.
An observer has detected and identified sample genetic materials by visually comparing the bands B3, B4, B5 and B6 of the sample regions 102, 103 and 104 with the bands B1 and B2 of the datum region.
In the above-mentioned current methods, the electrophoresis specimen should be visually observed to identify whether electrophoresis distances of the bands B3, B4, B5 and B6 of the sample regions 102, 103 and 104 agree with the bands B1 and B2 of the datum region 101.
However, the identification was hard to do in the following cases:
(1) Two bands are neighboring too close in the electrophoresis direction. PA1 (2) There are many number of bands in the datum region or the sample regions. PA1 (3) There are many number of genetic materials arranged in one (1) electrophoresis sample. If this is the case, the bands of the sample regions away from the datum region are hard to identify. PA1 (4) There is less amount of the datum genetic material or the sample genetic material. If this is the case, the bands formed are too small and light to identify. PA1 (5) There is large amount of the datum genetic material or the sample genetic material. If this is the case, the bands formed are too large to compare the electrophoresis distances, and two neighboring bands might overlap each other.
Despite these hardships, the identification of genetic materials must be done precisely. Accordingly, it takes rather long time to identify them.
Further intervals between two neighboring bands should be set longer to make the identification easier. Accordingly, the electrophoresis time becomes longer. Because the electrophoresis specimen should be made larger to set the electrophoresis time longer for easier identification, the identification time becomes longer and the identification cost increases.